Method and apparatus for lineup and register of printing plates



Nov. 11, 1958 R. E. FOGG METHOD AND APPARATUS FOR LINEUP AND REGISTER OFPRINTING PLATES 5 Sheets-Sheet 1 Filed Nov. 19, 1954 INVENTOR. ROBERT E.F066 HIS RTTORNEV5- Nov. 11, 1958 R E FOGG 2,859,532

METHOD AND APPARATUS FOR LINEUP AND REGISTER OF PRINTING PLATES FiledNov. 19, 1954 5 Sheets-Sheet 2 I 4 T a I "-34 i i I l L I L z i v f JZ Ia I fl INVENTOR.

ROBE ET E. FOG 6 HIS ATTORNEYS Nov. 11, 1958 R. E. FOGG 2,859,532

METHOD AND APPARATUS FOR LINEUP AND REGISTER OF PRINTING PLATES FiledNov. 19, 1954 5 Sheets-Sheet 3 ROBERT E. FOGG HIS ATTORNEYS Nov. 11,1958 R. E. FOGG METHOD AND APPARATUS FOR LINEUP AND REGISTER OF PRINTINGPLATES 5 Sheets-Sheet 4 Filed NOV. 19, 1954 INVEN TOR. 06587 5. F066 MawM. w-maver:

Nov. 11, 1958 R. E. FOGG METHOD AND APPARATUS FOR LINEUP AND REGISTER OFPRINTING PLATES 5 Sheets-Sheet 5 Filed Nov. 19, 1954 lllllll |||||||l\INVENTOR. 06727 4''. 066

BY Z

United States Patent METHOD AND APPARATUS FOR LINEUP AND REGISTER OFPRINTING PLATES This invention relates to a method and apparatus for thelineup and register of printing plates. This invention relates toregistering and lineup of plates in the letter press method of printing.However, the invention is not so limited in that the method andapparatus therefor may be used in other methods of printing and in otherprocesses.

In the art of printing, numerous problems have long existed in themake-ready operation of a multi-color press. In such type of printing,it is necessary to impress upon the paper web a plurality of colors inthe formation of a printed sheet. Upon a given plate cylinder aremounted a plurality of printing plates, the printing plates of eachplate cylinder being adapted to impress a definite color or colors uponthe web. After the paper web is printed on the first side, the web ismoved through a drying oven; then the web is printed on the second sidethereof. Between the time the paper web is printed on the first sidethereof and the second side thereof, a shrinkage occurs in the paperweb. As a result of this shrinkage of the 'paper web between the firstside impression and the second side impression, various problems arisein the registering and lineup of the plates on both the first side platecylinders and on the second side plate cylinders.

A great amount of time has been necessary in the past in the make-readyoperation in a multi-color printing ing plates which method andapparatus aid in greatly reducing the amount of make-ready time requiredin the preparation of a printing press for a given printing operation.

Another object-of this invention is to provide a method and apparatuswhich determine the proper position of printing plates while theprinting press upon which the plates are to be mounted is in operation.Thus, production may proceed during most of the make-ready operation.

Another object of the invention is to provide an apparatus foraccurately checking original engravings prior to the making of printingplates therefrom.

Still another object of the invention is the provision of an apparatusand method for checking various component parts used in fiat or curvedprinting work.

Another object of the invention is to provide a checking apparatus formachine parts and the like.

Another object of this invention is to provide a positioning apparatushaving a high degree of accuracy.

Other objects and advantages reside in the construction of parts, thecombination thereof and the mode of operation, as will become moreapparent from the following description.

In the drawings, Figure 1 is a perspective view showing a typicalmulti-color press unit provided with printing cylinders, packingcylinders and drying oven.

Figure 2 is an enlarged perspective view showing a fragment of a typicalplate cylinder and a printing plate adapted to be positioned upon aportion of the plate cylinder.

Figure 3 shows an enlarged view of a typical master card or indicatorcard of the apparatus of this invention.

Figure 4 is a lay-out view showing a plate cylinder for the first sideimpression and a plate cylinder for the second side impression laid outin'the fiat, each cylinder having one printing plate positioned thereon;this view also shows diagrammatically and somewhat exaggerated press.This make-ready operation includes the alignment and register of theprinting plates on the plate cylinders so that the first sideimpressions and the second side impressions are properly positioned onthe paper web. In other words, proper backup must be maintained. Alsoincluded in the plate positioning problem is the matter of locating theplates of the various cylinders so that proper color register isobtained.

Another problem in this type of printing operation results from the factthat the paper web may not be equal in width to the length of theattachment area of a plate cylinder used in the printing operation. Theattachment areas of the plate cylinders of most printing presses areinscribed with markings indicating positions for printing plates.Therefore, if there is a difference between the width of the paper weband the length of the attachment area, this difierence must beconsidered in positioning each printing plate with respect to theindicator markings upon the plate cylinder. This difference must beconsidered in properly positioning the printing plates on the platecylinders so that the impressions are correctly positioned upon thepaper web.

It is well known in the art of printing that the makeready operationusually involves a great amount of time. In the past, it has beennecessary to have a printing press out of operation during all of themake-ready procedure. Often the time involved in the make-readyoperation has been as great as or greater than the time involved in theprinting operation.

An object of this invention is to provide a method and an apparatus forthe lineup and register of printthe manner in which the paper webshrinks during its movement through the dryer oven.

Figure Sis a front elevational view with parts broken away of apositioning apparatus of this invention.

Figure 6 is a sectional view taken substantially on line 6-6 of Figure5.

Figure 7 is a front elevational view showing a preferred modification ofthe positioning apparatus of this invention, with a portion of thehousing therefor broken.

away.-

Figure 8 is a sectional view taken substantially on line 8-8 of Figure7.

Figure 9 is an enlarged diagrammatic exploded view showing the opticalsystem and light means in a scanner unit of this invention.

Referring to the drawings in detail, the diagrammatic perspective viewof Figure 1 shows a typical multi-color press unit provided with a firstside packing cylinder 20 having a plurality of first side platecylinders 22, 24, 26, 28 and 30. A paper web 32 contacts the first sidecylinders and moves into a dryer oven 34. The web 32 moves out of thedryer oven 34 and over a plurality of idler rolls 36. From the idlerrolls 36 the web 32 moves to a second side packing cylinder 40 and aplurality of second side plate cylinders 42, 44, 46, 48 and 50. Aplurality of idler rolls 53 aid in guiding the web 32 from the secondside packing cylinder 40.

Before the paper web enters the dryer oven 34, the paper web has a widtha, as shown in Figure 1. When the paper web moves from the dryer oven34, it has a width b, which is less than the width a due to the factthat a shrinkage of the paper web occurs during the drying operation. InFigure 4 is diagrammatically shown '3 a themanner in which the paper web32 shrinks in width as'the' web32 passes throughthe dryer oven 34.

As shown in'Figures 2 and4, each of the'plate cylin' ders may bedividedinto five equal longitudinal por tions-c, d, e, f and g-for theprinting-of five ribbons. 'l'he periphery of eachcy linder may be markedin four equaltransverse portions'h, i, j and k. Thus, the arcuateSurface of each plate cylinder may be marked in twenty equal rectangularplate attachment sections 51, each section'51'being adapted to receive aprinting plate, such as printing plate 54 M56. Each printing plate mustbe properly positioned upon its plate attachment section 51 of a platecylinder in order that proper printing on both sides of the paper webcan be accomplished.

A printed portion .on the first side of the Web '32 mustbeinalignmentwith a portion upon the reverse side of theweb 32 'inorder to'properlyform pages of printed matter; in other 'words, proper backup must bemaintained Furthermore, each color impression must correctlyreg'ist'er'with the other color impressions for the same page.

As stated above, in the past it has been necessary to expand aconsiderable amount of time in the make-ready operation beforethe'printing operation could be commenced. It has been a very diffic ultproblem due to the fact that the positioning of the printing plates,such as printing plates' 54- and 56, upon the plate cylinders has been amatter of guesswork and estimation or trial and error This invention hasprovided means and a' method by which the positioning of the printingplates upon platecylinders can 'be done quickly, easily and accurately.

Figure 2 is an enlarged view of a typical plate cylinder similar toanyone of the plate cylinders shown in Figure 1. The plate cylinder 60 isadapted to receive printing plates, such as a typical printing plate 62,to be attached thereto. 7 As shown in Figure 4, the arcuate surface ofeach of the plate cylinders is divided into twenty equal rectangularplate attachment areas or sections '51. Longitudinal centerlines .63 andtransverse centerlines 64 are marked through each of the twenty equalattachment sections 51. 'A 'printin'g' plate, such as the printing plate62, is adapted to be positioned upon one of the twenty equal sections51. Each printing plate 62 is provided with longitudinal center marks 66and transverse center marks 68.

If the width of the paper web 32 exactly coincided with thepositionmarkings for the printing plates upon the plate-cylinders, if noshrinkage would occur in the drying process between the first sideprinting and. the

secondside printing, and if other factors did not influencethepositioning of the, printing plates upon each'of the attachmentsections'51 of the plate cylinders, each printing plate would bepositioned so that the longitudinal center marks 66 and the transversecenter marks 68 of each printing plate would coincide withthelongitudinal centerlines 63 and the transverse centerlines 64respectively of its section 51. However, due to the fact that the widthof the paper web is not equal to the length of the attachment section asdetermined by the positioning inscriptions on the plate cylinder and dueto the fact that shrinkage does occur, and other problems are involved,each printing plate must be spaced so that the longitudinal center marks66 thereof are positioned inwardly or outwardly with respect to thelongitudinal center of the plate cylinder. Therefore, the longitudinalcenter marks of a plate do not necessarily coincide with thelongitudinal centerline of. the section 51 uponiwhich the plateispositioned.

In this invention a saddle is part of a positioning apparatus 75. Thesaddle 65 has an arcuate surface which is substantially the same incurvature as the surface of a plate cylinder. As shown in Figure 2, thesaddle 65 is similar to a segment 65a (shown in dotted lines) of thecylinder 60. The arcuate surface of thesaddle 65 is greater in area thanthe area of one; of the plate attachment areas 51. The positioningapparatus 75, is

used to determine-the proper location of a printing plate upon each ofthe areas 51 of a plate cylinder.

In regard to this invention, it has been learned that a paper web, suchas web 32, if approximately 70 inches in width, shrinks about one-fourthto three-eights of an inch during the drying process between the firstand second side printing. Considering that there are five equal spaces0, d, e, ;f and g along the length of each of the cylinders, the amountof movement of each printing plate upon the plate cylinder-to compensatefor web shrinkage may be calculated. For example, it may be determinedthat the printing plate 56 for the first ribbon position 0 on the secondside plate cylinder 42 should be moved inwardly, toward the longitudinalcenter of the plate cylinder 42, a distance of .187 inch to compensatefor the difference between the length of the attachment area of theplate cylinder and the width of the paper Web. It may also be determinedthat further movement of the printing plate 56 of .075 inch is. requiredas compensation for shrinkage of the paper web during the dry.- ingprocess. This makes a total movement of .262 inch of the plate 56 withrespectto the longitudinal center of its section 51 of the platecylinder. It may also be determined that the printing plate 54 for thefirst ribbon position c on the first side plate cylinder 36 must bemoved inwardly .187 inch from the longitudinal center of the section 51in order to compensate for the difference betweenthe width of the paperweb 32 and the printing plate positions as shown by the markings orvinscriptions on the plate cylinder. After it has been determinedtheexact amount that. each of the printing plates should be moved withrespect to the longitudinal centerline of its respective section of aplate cylinder, the positioning apparatus may be used to accuratelyposition each of the printing plates. v

The positioning apparatus 75 comprises a base 78 to which is securelymounted a block 32. atthe central portion thereof. Adjustably movableupon the block 82 is a carriage member 84 which is slidably secured tothe block 82. Firmly attached to the carriage member 84 is the saddle65, the arcuate surface of .whichhas a radius substantially equal to theradiusof curvatureof the stuface of one of the attachment sections 51 ofa plate cylinder.

' Also, attached to the base 78 is a bearing bracket 85 which rotatablysupports a threaded rod 86 which, is threadedly attached to the carriagemember 84-. An adjustment crank 88 attached to the rod 86 is providedfor rotation thereof. Preferably, the rod 86 and the carriage member 84are provided with fine threads so that adjustment of the carriagemember'm aybe made ,in thousandths of an inch or fraetions thereof.Naturally, the adjustment of-the carriage memberfi l with respect to theblock 32 is along the rotational axis of the threaded rod 86. .Along onelongitudinaledge of the. carriage member 84 is a gear rack 90. In meshedrelation with the gear rack 90 is a pinion gear 2 provided with avertical shaft 94. At the upper end of the shaft% is a bevel gear 96'cooperating with a' bevel gear 98v attached to a horizontal shaft 99,and also attached to the shaft 99 is an indicator finger 160 whichrotates about the center of an indicator disc 102. Supporting the disc102 and the shaft 94 is a support bracket 104. The indicator finger 100cooperating with the disc 102 thus indicates the movement of-thecarriage member 84 with respect to the block 82. The disc 102 may .bemarked in thousandths of an inch or fractions thereof.

Supported by thebase 78 are a plurality of vertical legs 105. Attachedat the upper end of the legs 105 is a cross support 106 to which isattached'a pair of camera and light projector combination units 108.Preferably, each of the camera-projector units 108 has a lens assembly109, a photo-slide holder 111, and a projector lamp 112 so that theassembly may beused either as a camera or as a projector, However, it isto be'u'nderstood that within the purview of this invention, each of theunits 108 may be a separate camera replaceable with a projector mountedin precisely the same position and angularly disposed in the same manneras the camera. Each camera-projector unit 108 is provided with aslidable cover 107 so that access to the slide holder 111 is readilyavailable.

A master card or indicator card 110, shown in Figure 3, is placed uponthe saddle 65 so that the master card 110 assumes the curvature of thesaddle'65. The master card 110 contains folio marks 113, color ad lines114, and bleed lines 116. The master card may also contain other typesof indicia or key markings.

Longitudinal center marks 117 and transverse center marks 119 arealigned with the longitudinal centerline 63 and the transversecenterline 64 respectively of the saddle 65. With the master card 110 sopositioned and the indicator finger 100 pointed to Zero, a photograph istaken of one-half of the master card with a film slide. disposed in eachslide holder 111. Naturally, during the photographing, the projectorlamp 112 is not energized. The light for taking the pictures may beprovided by a light source 115 attached to the cross support 106 or fromany other suitable source.

Thus, two pictures are taken, each picture showing one-half of themaster card 110 with the dividing line being at the center of thearcuate surface and normal to the arcuate edges thereof. The film slidesare then developed. These film slide negatives or other typetransparencies are replaced into the proper slide holders 111 and theimage of the master card projected therefrom; the image of the mastercard in its arcuate position, as positioned upon the saddle 65, is thusprojected by the light from the lamps 112 of the units 108, as shown inFigure 5. Light rays 120 emanating from each of the units 108 clearlyset forth the image of the master card 110 upon the saddle 65.

Before the make-ready process is begun, a chart is compiled showing thedistance from the center of each of the sections 51 that the printingplate to be attached thereto must be moved in order to compensate forthe various factors involved. As discussed above, some of the factorsinvolved are the difference in width of the paper web as compared to theplate positions indicated by inscriptions on the plate cylinder, andcompensation for shrinkage of the paper web which shrinks as it movesthrough the dryer oven.

As stated above, calculations may be easily made knowing that the paperweb shrinks a definite amount as it passes through the dryer oven andknowing the Width of the paper web as compared to the length of theplate attachment area of a cylinder as indicated by the plate attachmentindicator marks on the cylinder.

The saddle 65 which is firmly attached to the carriage member 84 isproperly positioned prior to the placing of a printing plate upon thesaddle 65. The saddle is properly positioned by turning the adjustmentcrank 88, thus moving the carriage member 84 with the saddle 65 attachedthereto until the indicator finger 100 cooperating with the indicatordisc 102 indicates that the saddle has been moved the total distancecalculated for compensation for the factors involved. Thus, the saddle65 is moved a given distance from the position which it occupied whenthe pictures of the master card were taken by the units 108. In otherwords, the saddle 65 is adjustably moved laterally with respect to thecameraprojector units 108.

For example, if it is known that the printing plate 62 should be alignedwithin the area 51 upon the cylinder 60, which it is to occupy, so thatthe transverse axis of the printing plate 62 should be displaced .262inch from the longitudinal centerline 63 of the rectangular area 51, thesaddle 65 is moved by the crank 88 until the indicator finger 100 readsupon the indicator disc 102 the value of .262. The printing plate 62 isthen placed upon the saddle 65, as shown in Figures 5 and 6.

With light rays 120 projecting the image of the master card from thecamera-projector units 108 upon the saddle 65, the printing plate 62 ispositioned upon the saddle 65 so that the folio or other indicia of theprinting plate 62 coincide precisely with the projected folio marks 113or other indicia of the master card 110. In the event the printing plate62 carries no folio, then ad lines or bleed lines may be used to alignthe printing plate with those portions of the image of the master cardprojected by the units 108.

After a printing plate, such as plate 62, is properly positioned uponthe saddle 65, as described above, a pair of scribe marks, such asscribe marks 121, are placed upon the plate 62. These scribe marks 121are provided for alignment with the centerline 63 of the section 51 ofthe plate cylinder 60 upon which the plate 62 is to be located. Thus, itmay be understood that an accurate method is provided by which aprinting plate may be properly positioned upon a plate cylinder. Thismethod provides means by which the proper position of a printing plateupon a plate cylinder may be determined within of an inch or closer.

In this invention means are also provided for obtaining proper andaccurate color register. In other Words, the printing plate 62 mayimpress the color black upon a given page of material. Other platesprovide impressions of one or more colors to the same page. In order toobtain proper register of these colors, it is necessary to accuratelyposition each printing plate for a given page in precisely the samerelative position upon its respective section 51 of the plate cylinder.After the first color plate 62 is properly positioned upon the saddle 65and is scribed with scribe marks 121, then means are employed toindicate the position of the plate 62 upon the saddle 65.

A definite letter or portion of a letter or some other point within theprinting plate 62 is aligned with a pointer 122 which is supported by anarm 124 held by a surface block 126. The light source may be used tocast a shadow of the pointer 122 upon a definite point on the plate 62.The surface block 126 and the pointer 122 remain in this preciselocation while the plate 62 is removed and is replaced upon the saddle65 by the next succeeding color plate for the same page. The same pointon this next succeeding printing plate is then aligned with the pointer122 so that this next printing plate is disposed precisely at the samelocation on the saddle 65 as was the printing-plate 62. Thus, all of theprinting plates positioned on the spaces around the periphery of acylinder for printing upon substantially the same area of a web may beaccurately aligned so that proper color register may be obtained.Furthermore, the impression of the first side printing is accuratelyaligned with the impression of the second side printing.

A preferred modification of the positioning apparatus of this inventionis shown in Figures 7, 8 and 9. A housing 130 encloses the positioningapparatus. Upon a floor 132 is a support block 134 to which is slidablyattached a carriage member 136. Rigidly attached to the carriage member136 is the saddle 65. As stated above, the saddle 65 is substantiallyidentical to a segment 65a of a typical plate cylinder 60. The carriagemember 136 is movable by means of a crank 138 which is similar to thecrank 88 of the preferred embodiment.

The crank 138 is used to rotate a rod 139 which threadedly engages aprojection block 141 of the carriage member 136. Axially attached to therod 139 at the end thereof is a shaft to which is attached a worm 142which drives an indicating finger 144. The indicating finger 144 isdriven by the worm gear 142 through a shaft 146 and a pair of bevelgears 150, as best shown in Figure 8. A disc scale 151 coo erates withthe indicatin" finger P e c 1:44 the relative. i Q .otthe saddle with 1P t he upport b1ock'1 34, I

"A l l perfiopr 152 rig' idly supports a pair of cameraprojecto r units153 whicligare siinilar to the camera-pro jector units 108 shown in thefirst described embodiment. An air blower unit 154 may be used to coolthe cameraprojector units'153 which may tend to heat considerably whenbeing used as a projector, due to the fact that a lamp 156 within theunit is lighted duringthe time that the unit is being employed asaprojector'.

In this preferred modification a scanner assembly is used to accuratelyindicatethe position of printing plates for the purpose ofobtaining'precise'color register. Upon the saddle 65 is positioned atypical printing ,plate, such as printing plate 62. As discussedab'o-ve,this printing plate 62 is herein described as being a first printingplate for one side of a given pagewhich is printed upon the paper web32. After the printing plate 62 is' properly positioned upon the saddle65 by use of light projection from the camera-projector units 153,it heprinting plate 62 is'scribed by means of scribe marksf121, as discussedabove, and the printing plate 62 remains in its proper position upon thesaddle 65 until this positionjis indicated and recorded by means of apair of scanninga'ssemblies 160.

Each scanning assembly 160 is movably carried upon a rail member'162which 'is' disposed on one side of the support block 134' Each ofthe rail members 162 extends substantially parallel to the rod member140. On each rail member 162 is movably positioned a magnetic carrierblock 164. "This magnetic carrier block 164 may be of a conventionaltype having a switch 166 which may be employed to rotate a magneticassembly within the carrier block 164 in order to magnetically secure orrelease the carrier block 164 upon its rail 162.

Firmly supported upon each carrier block 164 is an arcuate scannerbracket 168. Each scanner bracket 168 extends over the saddle 65 tosubstantially the center thereof, as shown in Figure 7. Upon eacharcuatescanner bracket 163 is adjustably positioned a scanner unit 170.Thus, it is understood that each scanner bracket 168 is movable alongthe length of the saddle 65. by means of the carrier block 164 upon itsrespective rail 162. Furthermore, each scanner' unit 170 is adjustablymovable upon its respective bracket 168 in a direction:transversc to therails 162. The scanner'units 170 ofthe preferred modification: replacethe pointer assembly having the pointer 122and'tl1e surface block 126shown in the first described embodiment. a

Each of the scanner units 170 may be positioned over a letter or .pointupon theprinting plate 62 positioned upon the saddlel65. 'A letter orpoint is chosen which appears upon all of the complementary color plateswhich together-impress. a given printed configuration. Each scanner ut"1 70 is provided with apair of substantially parallel legp'o'rtions171, and 1'72 joinedby a body portion 173 normal'tothe legs 171 and 172.The leg portion 172 is tapered, havinga lesser cross sectional area atthe juncture thereof ;than at the end thereof.

Within the leg 171 is a light source 174 and a light directinglens 176.The light-source 174 emanates light through the lens 176. This lightfalls upon an inclined mirror 178, mounted at the juncture of the leg171 and the body 173. The mirror 178 is provided with an aperture orunsilvered portion 180. The inclined mirror 178 directs light downwardlyupon the surface of a printing plate, such as the printing plate 62positioned upon the saddle65. Theaperture 180 within the mirror 17 8permits light rays to pass from the surface of the printing plate 62through a plurality of collimation lenses 182 which are mounted in thebody 173. The light rays pass through the collimation lenses 182 andreach a second inclined mirror 188, mounted at the juncture of the body173 and the leg.1 72. The mirror 188 directs rays of light to afrosted-lens or receiving screen 190 disposed at the end oftheleg172.

By this means a point,such as the corner of a .boat 194, which is partof a figure appearing on the printing plate 62, as shown in Figure 9, islighted by the lamp or light source 174 and light rays are .directedupwardly through the collimation lenses 1152. A greatly enlarged imageof this corner of the, boat is thus received upon the frosted lens 190,as clearly shown in Figure 9. Due to the fact that the printing platesare provided with a multiplicity of dot protuberances formingconfigurations offigures andletters for printing, these protuberancesappear as dots in the enlarged image on the frosted'lens 196.

By means of a crayon or the like, the image of this corner of the boatmay be traced upon the exterior surface of the frosted glass lens 190sothat the pattern remains upon the frosted glass lens even though theprinting plate 62 is removed from the saddle 65.

After the image of the corner of the boat is traced upon the frostedlens 190 of one of the scanner units 170, the other scanner unit 1'76 islined up with another point or letter on another portion of the arcuaiesurface of the plate 62. The image of this point or letter is tracedupon the frosted lens 190 of the second scanner unit in a manner similarto that described with respect to the first scanner unit. Therefore, thelocations of two points are accurately determined for the settingof theother complementary printing plates.

Each of the scanner units 170 is retained by a clamp 191 which isprovided with a clamping bolt 193. The bolt 193 extends through a guideslot 192 of the bracket 168. Thus, each scanner unit 171) is adjustablymovable upon its bracket 168. An entire scanner bracket 168 may be movedupon its respective rail 162 by means of the carrier blocks 164 whichmay be magnetically locked in a given position upon the rails 162 asdescribed above. The two arcuate brackets 168 may be joined one to theother at the ends thereof to form one large bracket with two scanningunits.

After the printing plate 62 has been aligned by means of thecamera-projector units 153 and two points on the surface thereof havebeen carefully indicated by means of the scanner units 170, the printingplate 62, having been scribed with scribe marks such as scribe marks'121,

is removed from the arcuate saddle 65. The next colorplate, whichcooperates with the plate-62 to provide one side of a page of coloredprinted material, is placed upon the arcuate saddle 65. This next colorplate has the same point or letter thereon such as the boat 194 shown,

in Figure 9. This corner of. the boat in the second color plate isaligned carefully with the first scanner 170 so that the image of thiscornerof the boat is carefully aligned with the outlines of the cornerof the boat which have beenmarked in crayon on the frosted lens 190, asshown in Figure 9. In other words, the outlines of the corner of theboat 194, drawn in crayon to indicate the position of the corner of theboat as shown by the position of the printing plate 62, are used toalign this same corner .of the boat appearing upon this second colorplate. to. the same position upon the saddle 65.

The second scanner unit is then used to line up the second point whichhas been chosen upon the plates. Thus, two points on the second plateare precisely located in the same positions upon the saddle 65 as thesame two points upon the plate 62 were positioned. Therefore, the secondcolor plate is precisely positioned in the same location as was theprinting. plate 62 upon the saddlel65. Then this second color plate. isscribed by marks; such ,as marks 121, to indicate the relative positionof this second plate with respect to the longitudinal center marks ofthe section 51 upon which itis tobe positioned.

, This same procedure is followed in determining the proper position ofall of the color plates which will cooperatev with the printing plate62. After all of the cooperating plates are individually located uponthe arcuate saddle ,65 and are precisely. scribed, the outline of themarking, such as .thea'corner of theboatll94iis erased from the frostedlens 190. Then another first color plate, such as plate 62, is alignedby means of the cameraprojector units and the same procedure is followedin indicating the position thereof by using the scanner assembly asdescribed above.

As shown in Figures 7 and 8, the housing 130 may support a pair of lampunits 195 which are located along the upper side portions of the housing130 and may be used in the photographing process. Another lamp 196 maybe located near the center portion of the housing 130 for use inilluminating the housing 130 when desired. An amber-color light 198 onthe like may also be supported by the housing 130 near the centerthereof to be used in the developing of a film used with thecameraprojector units 153.

-In some types of work it may be desired to use light projected from thecamera-projector units 153 for both the lineup and register of printingplates. In other types of work it may be desired to employ only scannerunits, such as scanner units 170, for checking various industrialoperations.

It is to be understood that, within the purview of this invention, othertypes of guide marks than scribe marks 121 may be used to indicateproper relative positions of printing plates upon the plate cylinders.Also, holes in the plate, or stops, may be used to indicate the properposition of the printing plates.

The method and apparatus of this invention may also beemployed for othertypes of work in the printing art. It may be used in flat plate work aswell as in cylinder plate work. The method and apparatus may also beused in the process of pre-register of original engravings for a moldingprocess. The method and apparatus of this invention may also be used inother types of industry than that of printing.

Although the preferred embodiment and modifications of the device havebeen described, it will be understood that within the purview of thisinvention various changes may be made in the form, details, proportionand arrangement of parts, the combination thereof and mode of operation,which generally stated consist in a device capable of carrying out theobjects set forth, as disclosed and defined in the appended claims.

Having thus described my invention, I claim:

1. A locator apparatus for printing plates comprising support structure,an arcuate saddle having substantially the curvature of a printingplate, the arcuatesaddle being longitudinally movable upon the supportstructure, a pair of projectors attached to the support structure, eachof the projectors being positioned for directing rays of light uponone-half of the arcuate saddle, and means for measuring the movement ofthe arcuate saddle upon the support structure.

2. A locator apparatus for indicating the longitudinal position of anarcuate printing plate upon a printing cylinder, the combinationcomprising a support structure, a pair of light projectors attached tothe support structure in spaced relation one from the other, acylindrical segment having its arcuate surface facing the projectorsmovably carried by the support structure, each of the projectors beingangularly positioned equidistant from the cylindrical segment so thatthe center of the projected light rays therefrom lies upon an extensionof a radial line of the arcuate segment, each of said projectors beingpositioned so that the projected light therefrom covers substantially anequal portion of the arcuate surface of the cylindrical segment, meansfor moving the cylindrical segment so that said segment remainsequidistant from each of the projectors, and means for measuring themovement of the cylindrical segment.

3. The method of marking printing plates for proper positioning of theprinting plates upon a printing cylinder provided with peripheralcentering lines normal to the axis of the cylinder, comprising the stepsof positioning an indicator card upon a cylindrical segment having anarcuate surface substantially identical to the arcuate surface of theprinting cylinder, the indicator card being provided with indicatormarks for a printing plate, followed by photographing the indicator cardpositioned upon the cylindrical segment, said photography being done bytaking two photographs, each photograph showing one-half of theindicator card, followed by removal of the indicator card from thecylindrical segment and by substituting for the indicator card upon thecylindrical segment a printing plate, followed by projectingtransparency photographs of the indicator card by light rays upon theprinting plate, the projecting being done from the positions and anglesfrom which the photographs were taken so that the light rays project theimages of the card upon the cylindrical segment at a position in whichthe printing plate should be disposed, followed by positioning theprinting plate in such position that said plate coincides with theindicator markings therefor projected by the light rays, followed byscribing the printing plate to indicate its position upon the printingcylinder.

4. A method of determining the position of a printing plate upon acylinder, the cylinder being provided with peripheral centering linesnormal to the longitudinal axis of the cylinder, comprising (a)positioning an indicator card upon a cylindrical segment, said segmentbeing equal to a segment of the cylinder, said indicator card assumingthe curvature of the segment, (b) photographing the indicator cardpositioned upon the cylin drical segment by a camera positioned in tworadial positions, each position permitting the camera to photographone-half of the card, (0) projecting images of the card upon thecylindrical segment, (d) placing a printing plate upon the segment, sothat the printing plate coincides with the projected image of theindicator card.

5. In a positioning device for printing plates comprising a base, anarcuate saddle mounted for relative movement with respect to the base,the arcuate saddle being movable along a line normal to a radial linethereof, a

support member carried by the base, a pair of projectors carried by thesupport member, each of said projectors being positioned and alignedupon an extension of a radial line of the arcuate saddle, the twoprojectors being positioned so that they are together capable ofprojecting direct light rays upon the entire curved surface of thesaddle, means for movement of the saddle, and means connected to thesaddle for measuring the movement thereof.

6. In a positioning apparatus for printing plates adapted to be locatedupon plate cylinders, a base, a saddle movably positioned upon the base,the saddle being equal to a segment of a plate cylinder, means formounting a plurality of projectors in spaced relation from the saddle,each of the projectors being positioned for directing light rays upon aportion of the saddle, and means for indicating the position of thesaddle with respect to the base.

7. The method of locating a printing plate upon a plate cylinder havingmarks for printing plate alignment comprising the steps of projectingimages of indicia upon a segment of a plate cylinder, followed by movingthe segment of the plate cylinder with respect to the projected images,followed by positioning the printing plate so that alignment occursbetween the projected indicia and the printing plate, followed bymarking the position of the printing plate with respect to the segmentof a plate cylinder, followed by placing the printing plate 7 upon theplate cylinder in accordance with the marks arig'ularl y di sposed" eachprojector-"being aligned upon a radial extension It oi the segment 'so'that light rays projected by eacheproj'ecftoi"fall'directly uponaportion-" of the 'arcu'ate""surface'of the segment, an indicator eard-for a printing"plate-; each of'tlte"projectors 'being adaptedto'projectan image of a portion of the'indicator card, and means foh'measuringlateral'movem-e'nt-of til i segment with respect to the projectors; Y

9. In a method of positioning'a printingplatempon" aretainer'member'f'or a printing operationythestepseofprojecting"alignment'indiciai by meansof lightrays upon asegment of the retainer inernber, followed by alignment of the'printingplate" upon: 'the*segment- -of the re-' tainer member with thealignm'ent' indicia'whichis pro-' jected upon the segmenfoftheretainermember, "fol lowed by indicating the position of-the printing plate withrespect to the segment of {the retainer member.

10; In a method of marking a printing platefor positioning of theprinting plate fupon-a retaineif'mernben fora printing operationythesteps ofprojecting alignment:v

indicia by means of light rays upon a segmentt ofnhe retainer member,followed by alignment "of the" printing plate upon the segment of theretainer member withtho alignment indicia which is projected upon'the'segmentof' the retainer member, followed by "scribing theposition oftheprinting plate with respect to the'position'of' thesegment oftheretainerrnember;

11.- In a method of marking a printing plate for positioning of theprinting plate upon a retainer member for a printing" operation,thesteps of projecting alignment in-' dicia upon a segment of theretainer member, the projecting means 'being'movable laterally withrespect to the segment of the retainer member, followed by relative"plate, the saddle member being movably attachedto the support block, apair of rails, the rails being mounted onopposite sides'of the supportblock, a scanner'bracket movable upon the 'ra'ilsya scanner-unitadjus'tably-antached to the scanner bracket, the scanner unit beinguiprovided with an optical lens and mirrorassembly and an-imagereceiving"lens, the optical lensand mirror assembly beingadapted to project'to theimage receiving lens-an'enla'rged image of a portion of a printin g'plate positioned upon the saddle member.

13; 'In 'a positioning apparatus-for printing platesj a I support blockmember, asaddle member for 'retainingf a printing plate, said membersbeing movably attached one to the other, a rail member extending:adjac'ent the support'blo'ck membe'r, a scanner bracket m'ovable upo'mtherail member,a scanner-unit adjustably attached to the scannerbracket,the scanner unit being provided withi a pair of leg portions,one' ofsaidleg portions h aving-a. lens assembly mounted therein, the other 'ofsaid 'leg por- -L tions 'having'a receiving lens at the end thereof,there: being aninclined mirror at the junctureof'the 'leg por tions. i

14. Ina positioning apparatus for-printingplates; the-combinationcomprising a support block,- a saddlet member for retaining a printingplate, the'saddle me'in her being movably attached to the supportblockpapain:- of rail members, one of said rail inembers 'beingmountedoneither side of the support block, a 'pairofsca'nne brackets, therebeing one scanner bracket movably at tached to each of said railmembers, a pair of' scanner units, one of said scanner units beingadjustablyattachedto each of said scanner brackets, each of saidscannerunits beingprovided with an opticallens andmir'ro'r as- "sembly,each of said scanner units also having an image receiving lens, theoptical lens and mirror es-- sembly being adapted to 'project'to theimage receiving lens an enlarged image ofa portion of a printing platepositioned upon the saddle member. a

15. A locator apparatusfor printing plates --compr'ising supportstructure, a saddle having a surface conform ing to the surface of aprinting plate, the saddle being 1 movable upon the support'structure, aplurality of projectors'attached to--the support structure; each or theprojectors hing-positioned for-directing rays of light upon a portion'of' thesaddle, andmeans for measuring the position 'of the saddle withrespect to the support structure; Y

16. A method ofdetermining the position'of -a print ing plate upon aholder therefor, comprising la) posi tioning an'indicat'or card upon abody having a surface similar to the surface of the holder, saidindicator card assuming the shape of the surface of the body, (11)photo-- 1 graphing the indicator card positioned upon the body by acamera positioned in spaced relation'from the body} (c) projecting animage of the card upon the-surface= of the body, (d) placing a printingplate up'on the bod-y? so that the printing plate-coincides with theprojected-'-'- image of the indicator car'd.-

